[messaging] On Signed-Only Mails

[Bjarni Runar Einarsson]

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Hi Trevor,

Thanks for your comments. A couple of questions!

Trevor Perrin <trevp at trevp.net> wrote:
> On Wed, Dec 7, 2016 at 11:36 AM, Bjarni Runar Einarsson
> <bre at pagekite.net> wrote:
> 
> You're relying on a different property: An attacker given
> (public key, message, signature) can't output a *different* key
> pair with a public key that also verifies the message.

Not "the message"... "all the messages."

The threshold is trivially configurable. Does that change
anything, or is it all the same? Or does nobody know since it
hasn't been well studied?

> But this is still a confused and risky use of signatures, IMO.

I see. How would you recommend I determine whether the whole
scheme is dangerous and should be abandoned, or if it's still
better than the status quo?

 - Bjarni

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